Field of the Invention
The present invention relate to an organic light emitting display (OLED) device and method of manufacturing the same, and more particularly, to an OLED device provided with a reflection preventing layer and method of manufacturing the same.
Discussion of the Related Art
An organic light emitting display (OLED) device includes a light emitting layer provided between a cathode for injecting electrons and an anode for injecting holes. When the electrons generated in the cathode and the holes generated in the anode are injected into the inside of the light emitting layer, excitons are produced by the recombination of the electrons and the holes. Then, when the excitons fall to a lower energy state from an excited state, the OLED device emits light.
Hereinafter, an OLED device according to the related art will be described with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view illustrating the OLED device according to the related art.
As shown in FIG. 1, the OLED device according to the related art may include a substrate 10, a thin film transistor 20, a passivation film 30, a color filter layer 40, a planarization layer 50, a first electrode 60, a bank layer 65, a light emitting layer 70, a second electrode 80, and a reflection preventing layer 90.
The thin film transistor 20 is provided on an upper surface of the substrate 10. The thin film transistor 20 may include a gate electrode 21 patterned on the substrate 10, a semiconductor layer 22 insulated from the gate electrode 21 by a gate insulating film 15 interposed therebetween, and source and drain electrodes 23 and 24 provided at a fixed interval from each other and provided on the semiconductor layer 22.
The passivation film 30 is provided on the thin film transistor 20.
The color filter layer 40 is patterned on the passivation film 30.
The planarization layer 50 is provided on the color filter layer 40. A contact hole is formed in a predetermined region of the passivation film 30 and the planarization layer 50, whereby a drain electrode 24 of the thin film transistor 20 is exposed via the contact hole.
The first electrode 60 is patterned on the planarization layer 50. The first electrode 60 is connected with the drain electrode 24 via the contact hole.
The bank layer 65 is provided on the planarization layer 50. The bank layer 65 is provided on a thin film transistor (TFT) region, to thereby define a display region.
The light emitting layer 70 is provided on the first electrode 60, and is patterned on the display region defined by the bank layer 65. The light emitted from the light emitting layer 70 passes through the color filter layer 40 and then the substrate 10, to thereby display an image.
The second electrode 80 is provided on the light emitting layer 70.
The reflection preventing layer 90 is provided on a lower surface of the substrate 10, to thereby prevent external light from being reflected on the lower surface of the substrate 10. As described above, the thin film transistor 20 is formed in the TFT region. Thus, the external light is reflected due to a plurality of signal lines for forming the thin film transistor 20. In this respect, the reflection preventing layer 90 is provided on the lower surface of the substrate 10 so as to reduce or prevent the reflection of the external light.
However, in the OLED device according the related art, the reflection preventing layer 90, which is typically provided in a film type, is formed in both the TFT region and the display region, which lowers the light transmittance of the display region and the luminance of the OLED device. That is, when the light emitted from the light emitting layer 70 of the display region passes through the substrate 10 and then the reflection preventing layer 90, a considerable amount of light is absorbed in the reflection preventing layer 90, thereby causing a light loss.